The present invention relates to a coupling for connecting various elements of a fluid flow system and is characterized in that it can be used with either an O-ring or with a packing for assuring a seal which prevents leakage of fluid flowing therethrough.
In the past it has been necessary to utilize one type of design for the coupling members when it was intended to utilize a packing for effecting a seal and a different design when utilizing an O-ring to effect such seal. As a result it was necessary for a user who had a need for valves or other items requiring couplings having packing type seals for some applications and O-ring type seals for other applications to maintain separate inventories of parts depending on whether such intended use required a coupling with a packing to effect the seal or an O-ring to effect the seal.